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Heat Advisory

Status

Event Extended (Time) Active alert

Start Time

Thu 08/21/2025 01:00 PM EDT

End Time

Sun 08/24/2025 12:00 AM EDT

Significance

Advisory

Impacts

Low impact

Full Alert Message

URGENT - WEATHER MESSAGE National Weather Service San Francisco CA 625 AM PDT Thu Aug 21 2025 ...HEAT ADVISORY NOW IN EFFECT FROM 10 AM THIS MORNING TO 9 PM PDT SATURDAY... * WHAT...Daytime temperatures in the 90s to low 100s expected. Nighttime temperatures in the low 60s in the Santa Clara Valley and upper 60s to mid 70s at higher elevations. * WHERE...The Santa Clara Valley and Eastern Hills, The East Bay Hills and Valleys, and North Bay Interior Mountains. * WHEN...From 10 AM this morning to 9 PM PDT Saturday. * IMPACTS...Hot conditions can cause heat illnesses. This level of heat affects most individuals sensitive to heat, especially those without effective cooling and/or adequate hydration. Impacts possible in some health systems and in heat-sensitive industries. PRECAUTIONARY/PREPAREDNESS ACTIONS... Hydration is a critical piece to surviving the heat. Drink water, and if possible, take water to those who are vulnerable. To reduce risk during outdoor work, the Occupational Safety and Health Administration recommends scheduling frequent rest breaks in shaded or air conditioned environments. Anyone overcome by heat should be moved to a cool and shaded location. Heat stroke is an emergency! Call 9 1 1. Beat the heat and check the backseat! Do not leave young children or pets in unattended vehicles. Car interiors will reach lethal temperatures in a matter of minutes.

Technical Header

CAZ504-510-513>515-220500- /O.EXT.KMTR.HT.Y.0004.250821T1700Z-250824T0400Z/ North Bay Interior Mountains-East Bay Interior Valleys-Santa Clara Valley Including San Jose-Eastern Santa Clara Hills-East Bay Hills- 625 AM PDT Thu Aug 21 2025